During the fabrication of automobiles, trucks, and similar over-the-road vehicles, many body components present structural members having cavities that require sealing to prevent the entrance of moisture and contaminants which can cause corrosion of the body parts. It is also desirable to greatly strengthen the members while maintaining their light weight. It is also beneficial to stabilize these members in order to attenuate noise that would otherwise be transmitted along the length or passage of the cavity. Many of these cavities are irregular in shape or narrow in size, thus making them difficult to properly seal and structurally reinforce.
Many attempts have been made to seal these cavities. Certain polymeric expandable sealing compositions have been proposed. However, many polymeric materials suffer from insufficient compressive strength. Certain reinforcing materials, such as glass fillers, have been proposed to provide additional strength. However, known processes of incorporating such high aspect ratio fillers into expandable sealing compositions typically degrade the reinforcer and its reinforcing properties. For example, in certain processes, glass fibers are combined, mixed, and heated with the solid polymeric resins. One drawback of such processes is that the glass fibers tend to break, resulting in shorter fiber lengths, less fiber entanglement, and poorer reinforcing performance. Thus, a need has arisen for a structural reinforcing composition and method of making the same which addresses the foregoing issues.